Coupling of Single Quantum Dots to Smooth Metal Films

July 20, 2009

Scientists at Argonne National Laboratory's CNM Nanophotonics Group have measured how light emission from individual colloidal semiconductor nanocrystals, or quantum dots, is modified when in proximity to smooth metal films.

Metal can strongly modify how emit light because of their coupling to electron oscillations in the metal, known as surface plasmons. Emission modification is important for the improvement of light-emitting devices, development of novel imaging techniques, and observation of novel phenomena, such as nanoscale lasing.

Quantum dots and metal nanoparticles can exhibit significant variation in size and shape, however, which makes it difficult to extract quantitative information. The new study alleviates this problem by employing single quantum dots near a smooth gold film. Even using single dots, measurements are difficult because of the well-known phenomenon of fluorescence , or blinking.

The CNM scientists developed a time-resolved single-photon counting technique to extract intrinsic emission rates, thereby resolving for the first time coupling between individual quantum dots and the metal surface.

Reference: X. Wu, Y. Sun, and M. Pelton, Phys. Chem. Chem. Phys. 11, 5867 (2009).

Provided by

Explore further: Single Atom Quantum Dots Bring Real Devices Closer (Video)

Related Stories

Single Atom Quantum Dots Bring Real Devices Closer (Video)

January 27, 2009

(PhysOrg.com) -- Single atom quantum dots created by researchers at Canada’s National Institute for Nanotechnology and the University of Alberta make possible a new level of control over individual electrons, a development ...

Recommended for you

Electrical circuit made of gel can repair itself

August 25, 2015

(Phys.org)—Scientists have fabricated a flexible electrical circuit that, when cut into two pieces, can repair itself and fully restore its original conductivity. The circuit is made of a new gel that possesses a combination ...

Biological tools create nerve-like polymer network

August 24, 2015

Using a succession of biological mechanisms, Sandia National Laboratories researchers have created linkages of polymer nanotubes that resemble the structure of a nerve, with many out-thrust filaments poised to gather or send ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.